Recovery of Phenyl Acetic Acid

Customer:	A leading pharmaceutical company.
Location:	Western India.
Tower Name:	Extraction Column.
Tower Diameter:	700 mm. 4 Packed Beds of 3m height.
Mass Transfer Equipment:	Medal-Pak tower packing and Liquid-Liquid Extraction internals.

History:
Client is engaged in pharmaceutical business for last 3 decades and has a major role in producing chemicals and drugs.

Process Overview:
In one of their propriety processes for antibiotic manufacture, the aqueous effluent from the plant contained significant amount of phenyl acetic acid, leading to loss of raw material and problems in the ETP. This was a major concern as it was found to violate the environmental regulations.

Customer Requirements:
1. Provide complete process solution for eliminating loss of phenyl acetic acid, considering existing capacity & future capacity enhancement plans.
2. Economize proposed project cost by utilizing existing spare column.

Problem analysis:

The client had employed mixer settlers to extract the Phenyl Acetic Acid (PAA) in Toulene which was not delivering the desired results.

Solutions provided:
Installation of Distillation or Extraction column was identified as possible solution for removing PAA from the effluent stream.

After collecting data from lab scale experiments on distribution coefficients of PAA in water and toluene, a detailed study of entire system was done.

The following was concluded & recommended:
1. Application of liquid liquid extraction.
2. Selection of Medal-Pak # 25 as a contacting media.
3. Selection & design of Liquid-Liquid Extraction Internals.
4. Selection of packed height to match required HETP.

Accordingly the tower internals were designed & manufactured along with random packing. The random packings & tower internals were installed & commissioned.

Results achieved:
The initial PAA concentration in the effluent stream was brought down to 100 ppm level and also the plant capacity was increased by 50%.